WOW, a Blu-Ray set! I'd say go for it. It sounds awesome and with all the extras of the V3 (including all the audio tracks I presume), it would be a worthy release. I believe it will look better than some early Blu-Rays....
By the way, OmegaMattman had the same idea and has made a 720p AVCHD of ESB. It's mentioned on this thread. You might want to check it out.